Key parameters at a glance
- A radius of 2.37 Earth radii
- A mass of 6.21 Earth masses
- Surface gravity around 1.11 g
- An orbital period of 3.827 days
- Semi-major axis 0.0410 AU
- Equilibrium temperature 798 K (525 °C)
- Distance from Earth 245.26 light-years
- Earth Similarity Index 0.324
- Travel time at Voyager 1 speed 4,325,169 years
- Almost certainly tidally locked to its host star given the close orbit
TOI-2133 b Planet Profile
Physical Specs
Classification
Planet Type
Sub-Neptune
Discovery
Size rank in cohort
Rank by radius
#1375of 1978
top 69.5%
This planet
2.37R⊕
Sub-Neptune median
2.71R⊕
Nearest-size peers
| Metric | Earth | TOI-2133 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 2.37 | 11.21 |
| Mass (M⊕) | 1.00 | 6.21 | 317.83 |
| Density (g/cm³) | 5.51 | 2.56 | 1.33 |
| Surface Gravity (g) | 1.00 | 1.11 | 2.53 |
| Insolation (S⊕) | 1.00 | 81.11 | 0.037 |
Star Catalogue Identifiers
TIC
TIC 39200363
Gaia DR2
Gaia DR2 1333818968701222272
Gaia DR3
Gaia DR3 1333818968701222272
System
TOI-2133
Percentile among Sub-Neptune cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 3.83 Earth days (1.0% of a terrestrial year) at a mean orbital distance of 0.0410 AU.
Transit Fingerprint
Depth
0.118 %
Duration
2.113 h
Impact parameter b
0.120
Rp / R★
0.035070
Transit midpoint (BJD)
2,458,985.8831
Photometric dip
Transit produces a flux drop of 1,182 ppm lasting ≈ 2.11 h.
Extended Orbital Architecture
Planet / star radius ratio
0.035070
Semi-major axis / stellar radius
14.170
Impact parameter (b)
0.120
Transit mid-time (BJD)
2,458,985.8831
Angular separation (arcsec)
0.54500
Eq. Temperature
798K
(525 °C)
Insolation (S⊕)
81.11
Earth = 1.00
Earth Similarity (ESI)
0.324
0 = alien, 1 = Earth-identical
Inside the inner HZ boundary (too hot for liquid water) — the surface is too hot to retain surface water. Close-orbiting tidally-locked around a cool host.
Discovery Paper
Primary reference
Morello et al. 2026Instrument
TESS CCD Array
Publication
2026-01
Observation locale
Space
Discovery cohort
Planets confirmed in 2026 at Transiting Exoplanet Survey Satellite (TESS) (12 shown).
Host System: TOI-2133
Spectral Class
K-type orange
Effective Temperature
4,250 K — cooler than the Sun (5,778 K)
Estimated Age
—
Stellar Radius
0.620 R☉
Stellar Mass
0.644 M☉
Metallicity [Fe/H]
-0.01
Extended Stellar Properties
Surface gravity (log g)
4.600 dex
Stellar density
3.680 g/cm³
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 11 bands
Astrometric Data
Parallax
13.269 mas
Total Proper Motion
66.786 mas/yr
PM Right Ascension
-17.88 mas/yr
PM Declination
64.35 mas/yr
Galactic Cartesian (pc)
x = -0.128 · y = -0.831 · z = 0.542
Equatorial (J2000)
RA 261.24383° · Dec 32.79840°
Galactic ℓ, b
56.500° · 31.506°
Ecliptic λ, β
256.824° · 55.838°
HTM-20 index
1030258174
Similar Worlds
Kepler-1814 b
Sub-Neptune · K-type orange
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TOI-1782.01
Sub-Neptune · K-type orange
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K2-233 d
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TOI-2443 b
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Kepler-1788 b
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Kepler-1214 b
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Radius 2.36 R⊕ · 2,378.4 ly